Bøker av Ladislav Ceniga

This book presents original mathematical models of thermal-stress-field interactions in two-component materials, which result from the superposition method, along with mathematical models of thermal-stress induced micro-/macro-strengthening and thermal-stress induced intercrystalline or transcrystalline crack formation. The mathematical determination results from mechanics of an isotropic elastic continuum. The materials consist of an isotropic matrix with isotropic ellipsoidal inclusions. The thermal stresses are a consequence of different thermal expansion coefficients of the matrix and ellipsoidal inclusions. The mathematical models of the thermal-stress-field interactions include microstructural parameters of a real matrix-inclusion composite. In case of a real matrix-inclusion composite, such numerical values of the microstructural parameters can be determined, which result in maximum values of the micro- and macro-strengthening, and which define limit states with respect to the intercrystalline or transcrystalline crack formation in the matrix and the ellipsoidal inclusion. This numerical determination is performed by a programming language.

This book presents original mathematical models of thermal stresses in composite materials, along with mathematical models of thermal-stress induced micro-/macro-strengthening and thermal-stress induced intercrystalline or transcrystalline crack formation. The mathematical determination results from mechanics of an isotropic elastic continuum. The materials consist of an isotropic matrix with isotropic ellipsoidal inclusions. The thermal stresses are a consequence of different thermal expansion coefficients of the matrix and ellipsoidal inclusions.The mathematical models include microstructural parameters of a real matrix-inclusion composite, and are applicable to composites with ellipsoidal inclusions of different morphology (e.g., dual-phase steel, martensitic steel). In case of a real matrix-inclusion composite, such numerical values of the microstructural parameters can be determined, which result in maximum values of the micro- and macro-strengthening, and which define limit states with respect to the intercrystalline or transcrystalline crack formation in the matrix and the ellipsoidal inclusion. This numerical determination is performed by a programming language.

This book presents analytical models of thermal stresses in two- and three-component composites with anisotropic components. Within the analytical modelling, the two- and three-component composites are replaced by a multi-particle-matrix and multi-particle-envelope-matrix systems, respectively. These model systems consist of anisotropic spherical particles (either without or with an envelope on the particle surface), which are periodically distributed in an anisotropic infinite matrix. The thermal stresses that originate below the relaxation temperature during a cooling process are a consequence of the difference in dimensions of the components. This difference is a consequence of different thermal expansion coefficients and/or a consequence of the phase-transformation induced strain, which is determined for anisotropic crystal lattices. The analytical modelling results from mutually different mathematical procedures, which are applied to fundamental equations of solid continuum mechanics (Hookes law for an anisotropic elastic solid continuum, Cauchys law, and compatibility and equilibrium equations). The thermal stress-strain state in each anisotropic component of the model systems is determined by several different solutions, which fulfill boundary conditions. Due to these different solutions, a principle of minimal total potential energy of an elastic solid body is then required to be considered. Results of this book are applicable within basic research (solid continuum mechanics, theoretical physics, materials science, etc.) as well as within the practice of engineering.

Part of the trilogy "Analytical Models of Thermal Stresses in Composite Materials I, II, III", this book proceeds from fundamental equations of Mechanics of Solid Continuum.

Deals with analytical models of thermal stresses in isotropic and anisotropic composite materials, represented by isotropic and anisotropic multi- and one-particle-(envelope)-matrix systems along with related thermal-stress induced phenomena represented by elastic energy fluctuations and thermal-stress strengthening.